Lifting device employing aerodynamic lift



" an-30,1968 HOULEZ-LW'WERE 3,36

LIFTING DEVICE EMPLOYING AERODYNAMIC LIFT Filed Dec. 7, 1965 3Sheets-Sheet l 1953 J. SOULEZLARIVIERE 3,366,347

LIFTING DEVICE EMPLOYING AERODYNAMIC LIFT 3 Sheets-Sheet 2 Filed Dec.'7, 1965 Jan. 30, 1968 J SOULEZ-LARIVIERE 3,366,347

LIFTING DEVICE EMPLOYING AERODYNAMIC LIFT Filed Dec. 7, 1965 3Sheets-Sheet s United States Patent 3,366,347 LIFTING DEVICE EMPLOYINGAERODYNAMIC LIFT Jean Soulez-Lariviere, La-Celle-Saint-Cloud-Yvelines,

France, assignor to Nerd-Aviation Societe Nationale de ConstructionsAeronautiques, Paris, France, a joint-stock company of France Filed Dec.7, 1965, Ser. No. 512,119 Claims priority, application France, Dec. 9,1964, 98,058 8 Claims. (Cl. 244-23) ABSTRACT OF THE DISCLOSURE AT-shaped lifting device of openwork type construction girders withcompletely faired air-screws and propulsion units which are located atone of the girder extremities so as to rotate about a commonlongitudinal axis of said girder. Three retractable under-carriage legsare located at girder extremities.

The present invention relates to a lifting device employing aerodynamiclift, and more particularly to a tripod lifting device which iscompletely faired.

Up to the present time, lifting devices have been proposed which havethe essential function of lifting from the ground a generally heavy andbulky load, but these devices most frequently employ, for reasons ofefiiciency, a propulsion device which is derived from the helicopter,and this device usually comprises a large lifting screw.

The free extremity of this air-screw rotor presents a certain amount ofdanger for the personnel in charge of the handling operations in theevent of an error of operation, but in particular it is risky for theair-screw itself in the case of movement of the apparatus over an areaencumbered with equipment or natural obstacles.

The danger thus inherent in the air-screw cannot be completelyeliminated, due to the fact that it is diflicult by fairing to protectan air-screw effectively which has the dimensions of a helicopter rotor,with respect to possible obstacles.

Furthermore, even if this were possible, this fairing would deprive thepilot of the machine of a substantial part of his visibility. Now, thepilots station should have a perfectly unrestricted view so as to enablethe pilot to carry out easily the necessary operations, both close tothe ground and during flight.

The object of the present invention is a lifting device with completelyfaired air-screws, eliminating all danger, both for the air-screw bladesand for the personnel in charge of the lifting operations on the ground,and which, by virtue of a particular arrangement of its control station,provides a perfectly clear panoramic view for the purpose of manoeuvreson the ground and during flight, under particularly ditficultconditions.

A lifting device according to the invention has the followingcharacteristics:

A propulsion unit comprising a number of faired airscrews is arranged ateach extremity of a first girder, each unit being capable of pivotingabout a common longitudinal axis of the said first girder, which iscoupled rigidly and perpendicularly at its central points to a secondgirder which forms a T-structure with the first girder.

The air-screws are arranged inside each of the two units in such mannerthat their thrusts are oriented in the same direction, the axes ofrotations of the air-screws being parallel to each other and located atequal distance and perpendicularly to the said common rotational axis ofthe said units.

Rotary power and thrust generators, turbo-propulsion units for example,are mounted alongside each other in the interior of each main unit, theaxes of rotation of the said generators being located in such manner asto intersect the said common pivotal axis and to remain parallel to theaxes of the air-screws, the residual reaction thrust having the samesense and direction as the thrust of the air-screws.

The structures of the first girder and the second girder are of openworkcross-bracing.

A single central mechanical coupling is provided between the generatorsand the air-screws.

Three retractable under-carriage legs of considerable height, two ofwhich are located forward, close to the extremities of the transversegirder, and the third at the free extremity of the longitudinal girder,carry wheels elastically coupled to the said legs, the two front wheelsbeing driving and steering wheels.

A control cabin is arranged between the rear leg and the longitudinalgirder, the field of vision being open in all directions, towards thefront, to the sides, upwards and downwards, and a control stationpermitting action to be effected by differential and overall variationon the pitch of the air-screws and on the speeds of the turbo-propengines.

The fairing of the air-screws is arranged so as to house the whole ofthe fuel.

It comprises the additional devices and apparatus usually employed onsimilar machines, in particular a lifting hook operated by a winch, thecable being located immediately below the centre of gravity of themachine and in the vertical plane of the said common pivotal axis.

The arrangement of the under-carriage legs is such that the supportingpoints of the two front legs on the ground are located in front of andtowards the exterior of the articulation points, so as to ensure amaximum passage track and on the other hand the largest possible base oflift on the ground.

Other characteristic features and advantages of the invention will bebrought out from the description given below, reference being made tothe accompanying drawings which give by way of example a form ofconstruction of a lifting device according to the invention.

In these drawings:

FIG. 1 is a perspective view of a tripod lifting device with aerodynamiclift, in the operating position on the ground;

FIG. 2 is a perspective view of one of the aerodynamic units of themachine shown in FIG. I;

FIG. 3 is a perspective view of the machine of FIG. 1 in flight, withoutload, and with the under-carriage legs retracted.

In accordance with a preferred form of embodiment of the invention, thetriangulated lattice structure of a lifting device with three legscomprises (see FIG. 1) on the one hand a transverse girder 1a having itsline of orientation y y' intersected perpendicularly at O by a plane ofsymmetry defined by the orthogonal axes y y' and Z and 2' and eachreceiving at its extremities a propulsion set 2d and 2g, which can pivotin the direction of the arrow about y y while their axis of symmetry canoccupy indifferently all the positions comprised between two adjacentorientations, one parallel to the axis x x' and the other parallel tothe axis Z0, 1' and further a longitudinal girder 112 having the line oforientation x x rigidly coupled to the cross-girder 1a and receiving atits free extremity a control cabin 3. The assembly is completed by twounder-carriage front legs 4g, 4d, pivoted about the axes x x and xparallel and symmetrically disposed with respect to x x and by a rearunder-carriage leg 5 articulated about an axis y y' parallel to y y'These three legs can be folded back in flight in the directions of thearrows f f so as to come into the position shown in FIG. 3. The frontlegs are inclined so as to move the supporting points B and B towardsthe front and towards the exterior of the vertical line of the fixingpoints, so as to increase on the one hand the surface of passagewayunder the machine and on the other hand the sides of the liftingtriangle zx/3-[3'. A hook 6 and a winch 7 located close to O areprovided for hooking the load 10, the trimming of which can be completedby slings 3.

In FIG. 2, there is shown the left-hand propulsion group 2g of themachine, but it is simple to deduce from this the right-hand propulsionset 2d, which is symmetrical to it. A single central transmission shaft11a, located on the axis y y' receives the rotary movement of the shaftsof the turbines of the prop units 12a, 12b (left-hand) and 12c, 12d(right-hand) and transmits this motion to the air-screws 13a, 13b(left-hand) and 13c, 13d (right-hand), through the intermediary of thegearboxes 14g (left-hand) and 14d (right-hand). Pivots 15g (left-hand)and 15d (right-hand), having their axes in y y' enable the propulsionunits to be pivoted, for

example in the direction 1, and ensure their coupling to the girder 1a.In the same way, the transmission of the differential pitch controls 16and the overall pitch 17 of the air-screws, together with that of thecontrol 18 for the speed of the turbo-prop engines is effected in thezones 19 by means of rotating joint devises or other similar apparatuswhich are usually employed for similar cases. A special arrangement ofthe fairings 20g (left-hand) and 20d (right-hand) provides the housingof the fuel 21.

For the purpose of simplifying the description, the usual and normalcircuits (lubrication, temperature and the like) have deliberately beenomitted from the drawings since these are Well known by those skilled inthe art and are applied in this case in conformity with industrialpractice.

The conditions required for the equilibrium of the machine are obtainedwhen the resultants of the thrusts of the air-screws in their variousinclinations pass through the axis y y' and when the centre of gravityis situated at equal distances from the said resultants and under theaxis 1Y0, y'a- In order to understand how the machine previouslydescribed can be manoeuvred, there are recalled below the conditions ofequilibrium which are necessary in order to carry out a verticaltake-off, a stationary flight, and a longitudinal movement in flight ofthe said machine.

For vertical take-off, the upward movement takes place when the generalresultant of the thrust reactions is greater than and in the oppositedirection to the force of gravity, all the forces being vertical.

Stationary flight is obtained when the general resultant of the thrustreactions with the force of gravity is zero.

Flight in longitudinal movement if obtained by simultaneous inclinationto the vertical of the two resultants of the thrust reactions of eachpropulsion group. This inclination has the effect of creating anon-vertical common resultant, for example longitudinal, resulting fromthe combination of the force of gravity with the said resultants.

The usual actions of piloting about the axes of pitching, yawing androlling are obtained by a differential or simultaneous inclination tothe vertical of the resultants of the thrust reactions of each group,associated or not with a differential or simultaneous variation ofthrust of the air. screws of each propulsion group.

All the operations which produce the above actions are obtained simplyby the differential or overall variation of the pitch of each air-screwand also by the differential or overall variation of the speed of theturbo-prop engines. The controls for these operations are quiteconventional for the type used to control propeller pitch and enginespeed. Control means 100 regulates the pitch of air-screw or propeller13a and control means 161 regulates the pitch of air-screw or propeller13b. The two symmetrical propellers in right-hand propulsion set 2d areregulated by another pair of similar control means. The speed of allfour turbo-propulsion sets is regulated by a single control means 102,for instance by a foot pedal (not shown). For simultaneously controllingthe inclination with respect to the vertical of the axis of symmetry ofeach of the propulsion groups, a pilot acts simultaneously on controlmeans 101 and the complementary control means to the opposite propulsiongroup or on control means 100 and its complementary control means to theopposite propulsion group. The speed of all engines is regulated by thesingle control means 102.

A typical example of an operation which the machine is capable ofeffecting consists of a rapid convoying with no load, followed byrepeated transfers of heavy or bulky loads 10. In FIG. 3, which showsthe machine during convoying without load, the legs 4g, 4d and 5 havebeen raised by means of suitable hydraulic jacks in order to reduce theaerodynamic drag. Similarly, it can be seen from FIG. 3 that the axes ofsymmetry of the propulsion groups have been inclined to the vertical, inorder to permit of lifting, together with propulsion, which is carriedout in horizontal flight. It is quite certain that this inclination canvaried, depending on whether the machine is unladenor whether it carriesa load, by virtue of the variation of the forces produced and of theeffect of air resistance on the load. Y

A lifting device with aerodynamic lift according to the invention offersthe following advantages:

By virtue of its faired air-screws, it permits of the approach withoutdanger to obstacles (masts, trees, etc.) which are generally encounteredduring work entrusted to this type of machine.

In the case of particularly heavy or bulky freight being handled, it hasavailable a large carrying capacity due to the effectiveness of thegroups of faired air-screws and by virtue of the arrangement of thestructural members permiting a wide and high passageway with aconsiderable free depth.

The visibility of the pilots station is excellent and gives asimultaneous view of the loading and the operating controls, togetherwith the whole of the machine and of the devices which control itsmanoeuvres.

i The construction is simplified as a result of the absence of the usualfailings such as fuselage, wings and tail unit.

Safety of operation during service is satisfactory by virtue of themechanical coupling of all the generators with all the air-screws. Afailure occurring on one or more generators always leaves a certaintotal power available, in fact proportional to the number of generatorswhich remain in operation.

The lifting device described above has been given by way of example andin order to explain clearly the advantages Which may be derived from theinvention. It will be understood that any modification may be made tothe invention in accordance with its scope, for example by modifying thenumber or the relative positions of the airscrews or power generators,the method of securing the load, or by applying the utilization of themachine to the lifting of a load from a position in stationary flight,or alternatively for the movement of a load suspended from the extremityof the cable.

I claim:

1. A lifting device comprising means for lifting from the ground andmoving with complete safety during flight a heavy and bulky load, saidmeans comprising a structure, a plurality of completely fairedair-screws, a piloting device in which the visibility of the pilot issubstantially ensured in all directions, and a hoisting device, saidair-screws divided into two propulsion groups respectively at the twoextremities of a first transverse girder of lattice construction, saidpiloting device comprising a cabin at the free extremity of a secondlongitudinal girder of lattice construction, the other extremity ofwhich is rigidly fixed to the centre of the first said transversegirder, the assembly of the two girders having the form of a T.

2. A lifting device as claimed in claim 1, in which each of saidpropulsion groups is adapted to rotate about a common axis of rotationalong the first said girder, and comprises at least two air-screwswholly encased by a common hood on their periphery, and at least twoturboprop propulsion units, said two air-screws having their individualaxes of rotation parallel and disposed on each side of said common axisof rotation, and the axes of symmetry of said two propulsion groupspassing through said common axis of rotation.

3. A lifting device as claimed in claim 2, in which the piloting devicecomprises, for each propulsion group, a control means for the overallair-screw pitch for the whole of the group and a control means for thedifferential airscrew pitch between the air-screws symmetricallyarranged on each side of said common axis of rotation.

4. A lifting device as claimed in claim 3, in which the piloting devicecomprises means for simultaneously controlling the inclination withrespect to the vertical of the axis of symmetry of each of thepropulsion groups, means for difierentially controlling, one withrespect to the other, the individual inclination of the two axes ofsymmetry of the two groups with respect to the vertical, means forcontrolling the speeds of the turbo-propulsion units, and means fortransmitting orders from the cabin to the mobile propulsion groups,passing through the zone of said common axis of rotation.

5. A lifting device as claimed in claim 4, comprising a commontransmission shaft centered on said common axis of rotation andtransmitting the total power of all the turbo-propulsion units of thetwo sets to two gearboxes located respectively on each group, saidgear-boxes each transmitting their movement to the two air-screws of thegroup.

6. A lifting device comprising means for lifting from the ground andmoving with complete safety in flight a heavy and bulky load, said meanscomprising a structure, a plurality of completely-faked air-screws, apiloting device from which the visibility of the pilot is substantiallyensured in all directions, and a lifting device, in which the air-screwsare divided into two propulsion groups respectively at the twoextremities of a first transverse girder of lattice construction, thepiloting device comprising a cabin at the free extremity of a secondlongitudinal girder of lattice construction, the other extremity ofwhich is rigidly fixed to the centre of said first transverse girder,the assembly of the two girders having the form of a T and comprisingthree supporting legs located respectively at each extremity of the armsof the T, said legs carrying pivoted wheels and being foldable into aretracted position by means of an articulation in the plane of the Twhen the machine is convoying without load.

7. A lifting device comprising means for lifting from the ground andmoving with complete safety in flight a heavy and bulky load, said meanscomprising a structure, a plurality of completely-faired air-screws, apiloting device from which the visibility of the pilot is substantiallyensured from all directions, said air-screws divided into two propulsiongroups respectively at the two extremities of a first transverse girderof lattice construction, the piloting device comprising a cabin at thefree extremity of a second longitudinal girder of lattice construction,the other extremity of which is rigidly fixed to the centre of saidfirst transverse girder, the assembly of the two girders having the formof a T and comprising three supporting legs located respectively at eachextremity of the arms of the T, said legs carrying pivoted wheels andbeing foldable into a retracted position by means of an articulation inthe plane of the T when the machine is convoying without load, the legslocated at the extremities of said first girder being situated at thefront of the machine and their wheels being displaced in front of thevertical plane containing their respective articulations, while the leglocated at the free extremity of said transverse girder is displaced tothe rear of the vertical plane of its articulation, this arrangementhaving the effect of providing simultaneously the largest possible baseof the triangular support and the widest possible passage between saidthree legs.

8. A lifting device as claimed in claim 1, in which each of saidpropulsion groups is adapted to rotate about a common axis of rotationalong the first said girder, and said hoisting device further comprisinga winch, a cable and a hook located substantially in the vertical lineof the centre of gravity of the lifting device and in the vertical planeof said common axis of rotation.

References Cited UNITED STATES PATENTS 2,997,258 8/1961 Purpura 244-233,170,530 2/1965 Black 7 3,176,939 4/1965 Mard 244l37 OTHER REFERENCESLife magazine, June 18, 1956, p. 109.

MILTON BUCHLER, Primary Examiner. T. BUCKMAN, Assistant Examiner.

